How to share a wifi password to another iPhone

Both iphones must run iOS11 or later AND you and your friend need to have each other listed as contacts in the Contacts app.

Example: at home, where you are already connected to your wifi network:

Your friend opens Settings>Wifi and taps on the name of your network (that should be listed among available networks)

You'll get a popup on your own iPhone that asks if you want to share your password. Tap "Share Password" and your Wi-Fi password is automatically sent to your friend's iPhone.

Regards

Giulio

Write it down on a piece of paper.

Why do you want to share your Wi-Fi password? Are both of these iPhones yours or is this other one someone else's and they need to know the password to access this Wi-Fi network?